In order to reduce costs, most engines used in the petroleum and natural gas industry on well sites do not have automatic starters. These engines must have a manual force applied to their flywheel in order to get them started. For years the manual force was applied by means of a crank. In more recent years the manual force has been applied by means of a friction applying engine starter. Friction applying engine starters have rotating wheels that are brought in contact with the flywheel. Friction is exerted by the rotating wheel of the engine starter rubbing against the flywheel of the engine imparts a rotational force to the flywheel causing the engine to start.
Friction applying engine starters that are currently in use are not very efficient. They have electric motors. The power to the electric motors is supplied from the battery of the service vehicle used by the maintenance crew through booster cables.